Move hasRuntimeTypeSupport, hasIsolateSupport, and hasFunctionApplySupport to JavaScriptBackend.

pkg/compiler/lib/src/js_emitter/program_builder/program_builder.dart

Index: pkg/compiler/lib/src/js_emitter/program_builder/program_builder.dart
diff --git a/pkg/compiler/lib/src/js_emitter/program_builder/program_builder.dart b/pkg/compiler/lib/src/js_emitter/program_builder/program_builder.dart
index 3fac2714d5fcf831a0f1176d2f1d8592d77424f4..1ee47ed582e66e944b7850e1de57dfbfc9c9c455 100644
--- a/pkg/compiler/lib/src/js_emitter/program_builder/program_builder.dart
+++ b/pkg/compiler/lib/src/js_emitter/program_builder/program_builder.dart
@@ -184,7 +184,7 @@ class ProgramBuilder {
         _buildTypeToInterceptorMap(), _task.metadataCollector, finalizers,
         needsNativeSupport: needsNativeSupport,
         outputContainsConstantList: collector.outputContainsConstantList,
-        hasIsolateSupport: _compiler.hasIsolateSupport);
+        hasIsolateSupport: backend.hasIsolateSupport);
   }
 
   void _markEagerClasses() {
@@ -675,7 +675,7 @@ class ProgramBuilder {
   }
 
   bool _methodCanBeApplied(FunctionElement method) {
-    return _compiler.hasFunctionApplySupport &&
+    return backend.hasFunctionApplySupport &&
         _compiler.closedWorld.getMightBePassedToApply(method);
   }